speed up for go

primes.go

@@ -9,11 +9,16 @@ import(
 	"math"
 )
 
+// In stead of in place printing of each prime, it seems 
+// fmt.Println is costly, and causes the program to take
+// 7x more time, so we gain speed at the expense of RAM
+// by storing them all in a slice and printing once
 func main() {
 	if len(os.Args) < 2 {
 		fmt.Println("Usage: go run primes.go [MAX]")
 		return
 	}
+	primes := make([]int, 0)
 	max,_ := strconv.Atoi(os.Args[1])
 	for i:= 3; i < max; i+=2 {
 		is_prime := true
@@ -24,7 +29,8 @@ func main() {
 			}
 		}
 		if is_prime {
-			fmt.Println(i)
+			primes = append(primes, i)
 		}
 	}
+	fmt.Println(primes)
 }